造林密度对南方红豆杉生长效应的影响

摘要

This study investigates the best approach to make full use of land productivity and obtain maximum eco-nomic benefits through the landscape cultivation of Taxus chinensis.We used a randomized block design of 5-year old plantations of eight different densities (160 000 trees/hm2 , 80 000 trees/hm2 , 40 000 trees/hm2 , 26 667 trees/hm2 , 20 000 trees/hm2 , 17 778 trees/hm2 , 13 333 trees/hm2 , and 10 000 trees/hm2 ) to analyze the effect of afforesta-tion density on young Taxus chinensis plantation growth.We specifically investigated plant height, ground diameter, and lateral branch number of Taxus chinensis.Results showed that the plant height, ground diameter, and lateral branch number in the eight afforestation density types are significantly different .Four afforestation density types of 20 000 trees/hm2 (0.5 m×1.0 m), 17 778 trees/hm2 (0.75 m×0.75 m), 13 333 trees/hm2 (0.75 m×1.00 m), and 10 000 trees/hm2 (1.0 m×1.0 m), showed significantly higher plant height and ground diameter than other affroesta-tion densities.Ground diameter and lateral branch number increased as afforestation density increased .The compre-hensive evaluation value of the afforestation density of 0.5 m×1.0 m was 0.592 7, which was the largest of all affor-estation density types and the proper afforestation density for the landscape cultivation of Taxus chinensis.%为充分利用土地生产力，通过园林景观式栽培南方红豆杉，以获得最大经济效益。采用随机区组设计，通过对5年生不同造林密度（160000株／hm2、80000株／hm2、40000株／hm2、26667株／hm2、17778株／hm2、20000株／hm2、13333株／hm2、10000株／hm2）南方红豆杉人工林的株高、地径与侧枝数量进行调查，分析了8种造林密度对南方红豆杉幼林生长效应的影响。结果表明，不同造林密度间南方红豆杉的株高、地径和侧枝数量的生长差异显著，其中20000株／hm2（0.5 m×1.0 m）、17778株／hm2（0.75 m×0.75 m）、13333株／hm2（0.75 m×1.00 m）和10000株／hm2（1.0 m×1.0 m）等4种造林密度的南方红豆杉株高与地径均显著高于其他造林密度，地径和侧枝数量随着造林密度的变小而呈增加的趋势；造林密度为20000株／hm2（0.5 m×1.0 m）的南方红豆杉生长性状的综合评价值为0.5927，是所有造林密度中最大的，以该密度营造南方红豆杉园林景观式栽培可以得到最大的经济收益。